The utility of LinkedIn very much depends on the field you are in. For software development it has been pretty useful. You should just add keywords for languages you know & want to work on. Don’t put down everything you know if you don’t want to work on it to reduce the number of job spam.
For my friend in engineering manufacturing, it was worthless. I can’t speak much to other jobs. I would just try to find IRL peers for you chosen job field and ask how they got their job.